http://vatoto.com/read/_/5250/until-death-do-us-part_v12_ch95_by_nihil-sine-nefas/11
If they slaughtered everyone except the teller whos left a mess, I think word spreading would backfire. Everyone would know they are going to be killed anyway, and take every opportunity to rush them, I know I would rush them if I knew they were going to kill me anyway.